The National Library of Medicine (NLM) is a national and international resource for biomedical information. Through use of the Library's computer-based Medical Literature Analysis and Retrieval System (MEDLARS(R)), users within the biomedical community receive timely, accurate and comprehensive bibliographic information. In addition to providing online retrieval services, MEDLARS is used for preparing and photocomposing bibliographic publications; INDEX MEDICUS(A), a monthly subject/author guide to articles in 3,127 biomedical journals, is the most well known of these. INDEX MEDlCUS is used as a primary reference source by medical institutions and health care professionals throughout the world. The objective of this project is to obtain editing, keyboarding, proofreading and online error correction of data that will enter MEDLARS. This project requires the processing of up to a maximum of 450,000 biomedical articles and 337,500 abstracts during the contract period.